Process of treating alkaline storage batteries.



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THOMAS A. EDISON, OF LLIEWELLYN PARK, NEW JERSEY, ASSIGNOR TO EDISONSTORAGE BATTERY COMPANY, OF WEST ORANGE, NEW JER- SEY, A CORPORATION OFNEW JERSEY.-

PHOCE$$ UF TREATING ALKALINE STORAGE BATTERIES.

Specification of Letters Patent.

Patented April 10, '1906.

Application filed September 29, 1904. Serial No. 226,487.

' Shipment-Thereof, of which the following is a description.

One of the difficulties that was encountered in the commercialexploitation of my improved iron-nickel storage battery was the' factthat in many instances cells failed in practice to reach the desiredstandard 'capac lty indicated by careful tests made 'rior to theshipment of the same from the factory. In these batteries, as is wellknown, the negative mass when char ed consistsof a mixture of reducediron 1111f metallic mercury. In the shipment of these cells theelectrolyte is removed [not only to reduce wei ht, but to prevent anydanger of its spilling out of the cell in transportation. After carefulinvestigation into the cause of the unsatisfactory operation referred toI have found that it is due to the fact that since the cells areship edin a partially-char ed condition a part 0 the iron mass is meta lic,which in the air becomes oxidized, resulting in the generation of heat,driving 0d the mercury more or less and reducing the conducting capacityof the negative mass. In order to overcome this defect, I com letelydischarge the negative mass by sen ing a reversingcurrent through thebattery, so that the iron is fully oxidized. Therefore no atmosphericoxidation can take place therein and no internal heating from thissource can arise. In this condition the battery may be transorted withentire safety with the electroyte removed and without any dan er of themercury being vaporized to there y affect the proper operation of thecell.

Having now described my invention, what I claim as new therein, anddesire to secure by Letters Patent, is as follows:

1. The process of treating, prior to shipment, an alkaline storagebattery, the nega-' tive mass of which contains when charged,finely-divided iron and metallic mercury, which consists in completelydischar ing the negative mass so as to fully oxidize t 9 same andprevent atmospheric oxidation, substantially as and for the purposes setforth.

2. Theprocess of treating, prior to shipment, an alkaline storagebattery, the negative mass of which contains, when charged,

finely-divided .iron and metallic mercury, which consists in sending areversing-current through the cell to completely oxidize the negativemass and prevent atmospheric oxidation, substantially as and for thepurposes set forth.

This specification si ned and witnessed this 26th day of Septem er,1904.

THOS. A. EDISON.

Witnesses FRANK L. DYER, ANNA R.

